Rotary power device

ABSTRACT

A rotary power device, usable as an engine or as a pump, comprising a rotary piston member concentrically mounted on a shaft within a cylindrical rotary runner member that is eccentrically mounted on the shaft, thus forming a closed, ringlike chamber of varying depth between the piston member and the runner member. The shaft, the piston member and the runner member are keyed together for conjoint rotation. Sliding vanes or other gate members are mounted in the piston member and project outwardly into engagement with the runner member, dividing the chamber into a plurality of chamber segments that vary continuously in volume, between maximum and minimum values, as the piston member and the runner member rotate.

United States Patent 91 Tauscher 51 Mar. 27, 1973 [54] ROTARY POWERDEVICE [75] inventor: Henry Tauscher, Oak Park, 111.

[73] Assignee: Impact, Inc., Chicago, 111.

[22] Filed: July 14, 1971 [21] Appl. No.: 162,421

[52] U.S. Cl ..418/173, 123/809 [51] int. Cl. ..F03c 3/00, F040 17/00[58] Field of Search ..418/l60,161,173, 175,185,

[56] References Cited UNITED STATES PATENTS 3,529,909 9/1970 Klover..418/173 3,256,831 6/1966 Eickmann ..418/173 3,318,291 5/1967Hallenbeck ..418/61 FOREIGN PATENTS OR APPLICATIONS 327,119 3/1930England 418/173 716,565 10/1931 France ..418/173 PrimaryExaminerClarence R. Gordon Attorney-James B. Kinzer et a].

[57] ABSTRACT A rotary power device, usable as an engine or as a pump,comprising a rotary piston member concentrically mounted on a shaftwithin a cylindrical rotary runner member that is eccentrically mountedon the shaft, thus forming a closed, ring-like chamber of varying depthbetween the piston member and the runner member. The shaft, the pistonmember and the runner member are keyed together for conjoint rotation.Sliding vanes or other gate members are mounted in the piston member andproject outwardly into engagement with the runner member, dividing thechamber into a plurality of chamber segments that vary continuously involume, between maximum and minimum values, as the piston member and therunner member rotate.

10 Claims, 14 Drawing Figures PATENTEDHARZ? ms FIG.)

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SHEET 6 OF 6 INVENTOR HENRY TAUSCHER ATTORNEYS ROTARY POWER DEVICEBACKGROUND OF THE INVENTION The rotary internal combustion engine haslong been recognized as a potentially efficient and light-weight sourceof power. Many different rotary engine constructions have been proposedin the past, but engines of this kind have rarely reached substantialcommercial acceptance. The proposed designs for engines of this kindhave ranged from simple devices with a quite limited number of movingparts to highly complex devices with literally hundreds of rotatingparts.

Most rotary engines have included a cylindrical stator encompassing arotary piston member, with the intake, compression, expansion andexhaust chambers for the engine disposed around the periphery of therotor. A critical problem in designs of this kind, re-

gardless of the means employed to define the limits of the variousengine chambers, arises from the necessity for sealing off the chambersfrom each other. Where effective sealing is accomplished, excessive wearon the sealing elements of the rotor or on the internal surface of thestator have usually resulted. Indeed, it has been said that the sealingdifficulty is the single most important problem that has preventedwidespread adoption of rotary engines.

ficult technical problem, often requiring relativelyfrequent replacementof the rollers, vanes, or other seal elements.

Another problem frequently presented in connection with rotary internalcombustion engines results from the fact that the combustion chamber isoften located at a fixed point on the stator. The result is localizedheating of the stator, with consequent thermal distortion and continuingthermal stress. This may result in erratic performance of the engine andultimate failure. Lubrication problems are also rather difficult, in atleast some rotary engine designs, with tentative solutions entailing theintroduction of oil into the combustion mixture or elaborate lubricationsystems intended to maintain the rotating parts of the engine inoperation.

There have been a few proposalsfor rotary internal combustion enginesthat have not incorporated a stator, a least in the usual sense of theterm. One example of a rotary internal combustion engine that utilizestwo rotating elements instead of the usual rotor and stator is Nixon,US. Pat. No. 1,777,932, incorporating a cylindrical outer rotor memberhaving two axially displaced internal compartments, and a two-elementinner rotor eccentrically mounted within the two compartments of theexternal rotor. In the Nixon engine,however, the sealing problemprevalent 'in more conventional designs for rotary engines is stillpresent, since there is a relatively large range of movement between theinternal and external rotor elements. Furthermore, localized heating ofthe engine parts is inevitably present, due to the combustion firingarrangement employed in the engine. Another proposed engine that did notuse a conventional stator, but employed plural rotating members, was anearly version of the engine commonly referred to as the Wankel engine,as described in Popular Science, March 1960, pages 82-86, andparticularly page 85. Again, however, the same sealing problem that hasplagued rotary engines is presented, due to a large range of relativerotational movement between the inner and outer rotors of the engine.Moreover, localized heating was also likely in this engine. The Wankelengine was subsequently modified to incorporate a stationary externalmember instead of an external rotor.

SUMMARY or THE INVENTION It is an object of the present invention,therefore, to

provide a new and improved rotary internal combustion engine that iscompact, light in weight, and capable of high power output, and thateffectively minimizes or eliminates the problems and difficulties ofpreviously known rotary engines.

A specific object of the invention is to provide a new and improvedconstruction for a rotary power device, suitable for use as either anengine or a pump, that effectively minimizes friction between theprincipal elements of the device by limiting relative movementtherebetween to an exceedingly small range.

Another object of the invention is to provide a new and improved highpower rotary engine that includes no stator and that permits the use ofmultiple firing points to equalize heating effects-aroundthe peripheryof the engine.

A specific object of the invention is to provide a new and improvedrotary power device, suitable for use as a pump or as an engine, thathas minimal lubrication needs and is capable of sustained operation overlong periods of time and at heavy loads.

Another object of the invention is to provide a new and improved rotaryinternal combustion engine that can be operated in any desiredorientation, that is, with the shaft extending at any angle from thehorizontal to vertical.

A rotary power device constructed in accordance with the inventioncomprises a frame, affording at least one bearing support aligned with aprimary axis, and a runner member mounted on the frame for rotationabout the primary axis; the runner member has a central opening ofgenerally cylindrical configuration and includes end walls closing offboth ends of the central opening. A shaft is mounted on the frame forrotation about the primary axis. A piston member is mounted within thecentral opening in the runner member, the

end surfaces of the piston member being disposed in close sealingrelation to the inner end surfaces of the runner member. The peripheralsurface of the piston member and the internal surface of the runnermember are symmetrical with respect to axes that are parallel to butdisplaced from each other, and one of those surfaces is symmetrical withrespect to the primary axis, so that the peripheral surface of thepiston member and the internal surface of the runner member define aclosed ring-like chamber varying in radial depth from a minimum ofvirtually zero along a given radius from the primary axis to a maximumdepth at the opposite radius from that axis. Fluid inlet and outletopenings are provided, communicating with the aforesaid chamber. Aplurality of gate members are mounted in the piston member for limitedradial movement; the gate members project radially outwardly of thepiston member, through the chamber and into engagement with the innersurface of the runner member. Each gate member extends for the fulllength of the central opening in the runner member so that the gatemembers divide the aforementioned chamber into a corresponding pluralityof chamber segments. The shaft, the runner member, and the piston memberare all interconnected, by key means, for conjoint rotation about theprimary axis, so that the effective volume of eachchamber segment variescontinuously between a minimum and a maximum as the device rotates.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation view of arotary power device, specifically a rotary engine, constructed inaccordance with one embodiment of the present inven- FIG. 5 is asectional view taken approximately along line 5-5 in FIG. 2;

FIG. 6 is a detail sectional view taken approximately along line 6-6 inFIG. 2;

FIG. 7 is a detail sectional view of a modification for the intake ofthe engine, taken approximately as indicated by line 7-7 in FIG. 2;

FIG. 8 is a detail sectional view of a part of the engine exhaust;

FIG. 9 is a sectional side elevation view, similar to' FIG. 2, ofanother embodiment of the invention;

FIG. l0.is a sectional elevation view, taken approximately along line10- 10 in FIG. 9; and

FIG. 11 is a sectional elevation view, generally corresponding to FIG.5, of yet another embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. l6 illustrate a rotarypower device, constructed in accordance with one embodiment of thepresent invention, constituting a rotary internal combustion engine 20.Engine comprises a frame generally designated by reference numeral 21and including a base plate 22 upon which two bearing pedestals 23 and 24are mounted by suitable means such as the bolts 25. Pedestal 23, therear pedestal of the engine, is preferably formed as a metal casting.The front pedestal 24 is also preferably a metal casting.

' The rear pedestal 23 includes a horizontally oriented opening 26within which a bearing support member 27 is mounted. Bearing supportmember 27 includes a bearing cavity 28 within which a rear main bearing,a roller bearing 29, is mounted; the inner wall of cavity 28 affords theouter race for bearing 29. Roller bearing 29 comprises an inner race andcage member 31 and a multiplicity of roller elements 32. Roller bearing29 is concentrically aligned with a primary axis 33. The inner racemember 31 of bearing 29 is affixed to an engine shaft 34 that extendslongitudinally of engine 20, shaft 34 being concentric with respect toaxis 33.

The front pedestal 24 of engine 20 has a horizontally oriented opening36 within which a front bearing support member 37 is mounted. Bearingsupport member 37 includes a horizontally oriented bearing cavity 38affording the outer race for a second main roller bearing 39.- Bearing39 also comprises an inner race and cage member 41 and a multiplicity ofindividual roller elements 42. The outwardly facing end of pedestal 24is covered by a face plate 43, through which shaft 34 projects to permitcoupling a load to the engine.

A runner member 45 is incorporated in engine 20 and is mounted upon theframe pedestals 23 and 24 for rotation about the primary axis 33 of theengine. Runner member 45 comprises a generally cup-shaped element 46having a front end wall 47. An end wall member 48 is mounted on the rearof the cup-shaped runner element 46 to afford a runner member having acentral opening 49 of generally cylindrical configuration. The centralopening 49 in the runner member, however, is not symmetrical with theprimary axis 33 of engine 20. Rather, the central opening 49 issymmetrical with a secondary axis 51 which is parallel to but displacedfrom the primaryaxis of the engine, as best shown in FIGS.'2 and 5. Thatis, the central opening 49 in runner member 45 is eccentrically locatedwith respect to the axis of rotation of the runner member, the primaryaxis 33.

The mounting for runner member 45 comprises a pair of roller bearings 52and 53 mounted in the runner end walls 47 and 48, respectively. Theinner race for roller bearing 52 is afforded by a hub 54 that is anintegral part of the bearing support member 37 (FIG. 2). Similarly, theinner race for roller bearing 53 comprises a hub 55 that is an integralpart of the bearing support member 27.

As most clearly shown in FIG. 2, shaft 34 extends completely through thecentral opening 49 in runner member 45. A piston member 56 is mounted onshaft 34, within the confines of the central runner opening 49. Thefront and rear end surfaces 57 and 58 of piston member 56 are disposedin close sealing relation to the inner end surfaces of the runner walls47 and 48, respectively. The peripheral surface 59 of piston member 56,which in this instance is of circular configuration, is symmetrical withrespect to the primary axis 33 of the engine (FIG. 5). Consequently, theperipheral surface 59 of piston member 56 and the inner surface 61 ofrunner member 45 define a closed Engine 20 further comprises four gatemembers 62,

63, 64 and 65 each mounted within a radial slot in H piston member 56,as most clearly shown in FIG. 5. Gate member 65, which projectsvertically downwardly from axis 33 when the engine parts are oriented asshown in FIG. 5, extends for the full length of the central opening 49in runner member (FIG. 2). Similarly, each of the other gate members 62,63 and 64 3xtends forthe full length of the piston and hence from oneend wall to the other end wall of the runner member. Moreover, the gatemembers are all biased outwardly from axis 33, by internal springs 66,so that each gate member engages the inner surface 61 of runner member45. Suitable sealing elements 67 may be provided along the sides of gatemembers 62-65 (FIG. 5); edge seals 68 for the ends of the gate membersand for the end surfaces 57 and 58 of piston 56 may also be employed.Consequently, the gate members divide the ring-like chamber aroundpiston member 56 into four separate chamber segments 72, 73, 74 and 75(FIG. 5).

For effective operation of engine 20, it is necessary to provide somekey means to interconnect shaft 34, runner member 45, and piston member56 for conjoint rotation about the primary axis 33 of the engine. Pistonmember 56 may conveniently be press fit, keyed, spline fit, or otherwisefixedly mounted directly on shaft 34.

Runner member 45 may also be connected directly to shaft 34. In engine20, however, the keying connection for runner member 45 is effectedbetween piston 56 and runner member 45. A series of pins 77 are mountedon the ends of the gate members 62-65 of 7 piston member 56. Each pin 77extends into an elongated radial slot in the adjacent side wall ofrunner member 45, as shown by the phantom slot outlines 78 in FIG. 5.The radial slots 78 are provided for pins 77 because the radialdisplacement of the pins, relative to runner member 45, changesconstantly during rotational movement of the engine. Slots 78, inaddition to being elongated, should be widened at their central portionsto compensate for very limited angular dis placement of runner 45 andpiston 56 (usually of the order of 6 to 12") during operation of theengine.

A front cover plate 81 of flattened cup-like configuration is mountedupon runner 45, covering the outer surface of the runner end wall 57 anddefining an exhaust chamber 86 between the medial portion of plate 81and the medial portion of end wall 47 of runner member 45. The runnerend wall 47 is provided with four exhaust valve openings 82, 83, 84 and85 aligned with the working chamber segments 72, 73, 74 and 75respectively; the location of openings 82-85 is indicated in FIG. 3, andtwo of the openings 82 and 84 appear in FIG. 2. Each of theopenings82-84 provides a housing for an exhaust valve that communicateswith the exhaust chamber 86.

One construction that can be utilized for the exhaust valves is shown inFIGS. 2, 2A and 4. As shown in FIGS. 2 and 2A, the exhaust valve 87 thatis mounted in opening 84 includes a fixed front valve plate 88 mountedin the inner part of opening 84. Valve plate 88 has four radiallyextending openings 91 of relatively narrow configuration. Behind valveplate 88 there is a second valve plate 92 which is mounted upon a valveshaft 89. The second valve plate 92 has four radial openings 93. Withthe valve plates oriented in the position shown in FIG. 2A, the valve 87is closed. By turning shaft 89 and plate 92 through a relatively smallangle, less than 45, the openings in the two valve plates 88 and 92 canbe aligned with each other, thereby opening valve 87 FIG. 4 illustratesthe operating mechanism for valve 87. As shown therein, the valve shaft89 carries a cam follower 94 which is affixed to shaft 89 by a pin 95that extends outwardly of the cam follower at one side of the shaft. Camfollower 94 engages a cam track 96 on a ring cam member 97. A spring 98is connected tocam follower 94 and to cover plate 81, biasing the camfollower into engagement with track 96 and urging the cam follower andshaft 89 toward rotation in a counterclockwise direction as seen inFIGS. 3 and 4. A stop pin 99 mounted on cover plate 81 is positioned forengagement by pin 95, and limits the clockwise rotation of cam follower94 and valve shaft 89. As seen in FIG. 4, when the cam follower 94reaches an enlarged diameter portion 101 on cam track 96, spring 98pivots cam follower 94 and shaft 89 in a counterclockwise direction, themovement being limited by engagement of stop pins 95 and 99. Thisrotational movement of shaft 89 effects a corresponding rotation ofvalve plate 92 (FIG. 2A), aligning'the valve openings 91 and 93 to openexhaust valve 87. Similar valve structures are provided in each of thefour exhaust valve openings 82-85 (FIG. 3).

The inner central portion of the exhaust cover plate 81 is disposed inencompassing relation to hub 54 of bearing support member 37 and issealed to the hub by suitable means such as an O-ring 102. Hub 54 isprovided with an enlarged central opening or flue 103 (FIGS. 2 and 6). Apassageway 104 connects exhaust chamber 86 into flue 103. Thus, wheneverone of the exhaust valves is open, a connecting passageway is completed,through chamber 86, passage 104 and flue 103, into an exhaust chamber105 in front pedestal 24.

.The construction at the rear end of engine 20 is similar to butspecifically different from that at the front end of the engine. Therear end wall 48 of runner member 45 is provided with four intake valveopenings, similar to the exhaust valve openings 82-85 in wall 47; two ofthese intake valve openings 112 and 114 are shown in FIG. 2. Each of thevalve openings in the rear end wall 48 of runner 45 houses a rotaryintake valve corresponding in construction tothe exhaust valve 87described above in connection with FIGS. 2, 2A, 3 and 4. The camfollowers of the intake valves engage a cam ring 115 that is similar inconstruction to the cam ring 97 employed for the exhaust valves. A rearcover plate 116 of flattened cup-like configuration is mounted upon therear end wall 48 of'runner member 45 and defines an intake chamber 1 17between the runner end 'wall 48 and the cover plate 116. Thecentralporti'on of cover plate 1 16 is disposed in encompassing relationto the hub 55 of bearing support member 27 and is sealed thereto byappropriate means such'as an O-ring 118.

I-Iub 55 includes an enlarged central opening I19 that communicates withthe intake passage 117 through an aperture 121. The rear end of shaft 34is hollow, and the interior of the shaft communicates with hub opening 119 through a plurality of apertures 122 in the shaft. The outboard endof the hollow shaft is connected, through a series of radial openings123 in the shaft, with an intake passage 124 in a carburetor mount rearpedestal 23. A carburetor may be mounted above passageway 124 byappropriate means comprising the tapped bolt-receiving holes 128. Theintake passageway 124 is sealed by means of suitable seals such as theO-rings 126 around the periphery of the outboard rear end of shaft 34. Asafety plug 127 closes the outboard end of the hollow portion of shaft34.

Provision may also be made for supercharging of engine 20. Thus, asshown in FIG. 7, the carburetor mount 125 may be provided with anadditional intake passageway 131 for connection to a source of highpressure air for supercharging purposes. Passage 131 is disposed atright angles to the main intake passage 124 through which the fuelmixture is introduced into the engine.

Provision may also be made for a high efficiency exhaust system forengine 20. As shown in FIGS. 2 and 3, the exhaust chamber .105 in frontpedestal 24 is connected to an exhaust-conduit 132. Conduit 132 may beconnected to the usual muffler and thence to the atmosphere; anyappropriate form of exhaust purification system, including a catalyticafterburner, may be employed as desired. As shown in FIG. 8, exhaustconduit 132 extends only partly through the width of chamber Inconsidering the operation of engine 20, it'may be assumed that runner 45and piston 56 start from the position shown in FIG. 5. Rotation of theengine is in a clockwise direction as viewed in FIG. 5. The intake valvefor chamber segment 75 has previously been open, admitting an air-fuelmixture into chamber segment 75 through the passages and openings 124,123,

122, 119, 121 117 and 114 (FIG. 2). The intake valve in opening 114closes about the'time that the runner and piston reach the positionshown in FIG. 5.

Continuing rotation of piston 56 and runner 45 drives gate member 65inwardly of piston member 56; after 90 of rotation, gate member 65reaches the position occupied in FIG. 5 by gate member 62. This samerotation reduces the volume of chamber segment 75 from that shown inFIG. 5 to the volume shown in the drawing for chamber 72. Thus, thefuel-air mixture inchamber segment 75 is compressed. Continuing rotationof runner 45 and piston 56 brings chamber 75 to the position occupied inFIG. 5 by chamber 73. At this 7 point, the spark plug 145 for chamber 75engages the electrical contact 146, igniting the mixture of air and fuelin chamber segment 75. As the air-fuel mixture burns, it increases thepressurefwithin the chamber segment and exerts a substantial forceagainst the lead gate 105 in pedestal 24. The open inner end of exhaustconduit 132 encompasses a tapered nozzle 133 connected to a conduit 134that extends outwardly of the opposite wall of pedestal 24 and isconnected to a high pressure air supply. Nozzle 133 and conduit 132afford a venturi or jet pump to assure rapid and effective scavenging ofexhaust gases from chamber 105.

Engine 20 is provided with ignition means comprising four spark plugs142-145, one for each of the chamber segments 72-75. Each of the sparkplugs is mounted in a radial opening runner 45, preferably at thelongitudinal center of the runner (see FIG. 1), the spark plug openingseach communicating directly with the associated chamber segment. A fixedelectrical contact 146, connected to a suitable electrical supply, ismounted in position to engage each of the spark plugsas runner 45rotates during operation of engine 20 (FIG. 5), completing the ignitionsystem.

Because spark plugs 142-145 are mounted in fixed positions in runner 45,it is desirable to provide some means for adjusting the openingpositions for the intake 62 for chamber 75, tending'to drive the gatemember in a direction to continue the clockwise rotation of pistonmember 56. Since piston 56 and runner 45 are compelled to rotateconjointly, by the key connection afforded by pins 77 and slots 78, thesame force is applied to runner 45 and both the runner and pistoncontinue their rotational movementwith the additional impetus affordedby the burning of the fuel in chamber 75.

The continuingrotation of engine 20 brings chamber 7 75 to the positionshown in FIG. 5 forchamber segment 74. At this time, the exhaust valvefor chamber 75 is 7 opened and the hot gases from the chamber are exandexhaust valves of the engine in order to adjust the engine timing. Asnoted above, the actuation of the exhaust valves is controlled by thecam track 96 on the exhaust cam ring 97. Cam ring 97 is supported uponan arcuate support member 148 that is affixed to the lower portion ofpedestal 24 by suitable means such as bolts 149. Cam ring 97 is securedto support member148 by a plurality of bolts 150, each engaged in anelongated slot 151 in support member 148 and each threaded into a tappedopening in ring 97. To adjust the exhaust valve timing,.therefore, it isonly necessary to loosen the bolts 150, rotate the cam ring 97 to modifythe timing. as required, and again tighten the bolts. Suitable lockwashers may be employed to prevent shifting of the ex-.'

haust timing cam 97 during operation of the engine. A similar mountingarrangement (not shown) is employed for the cam ring 115 that controlsthe actuation and timing of the intake valves. For either of the two camrings, a balanced support engaging both sides ofv the ring may beutilized if desired.

hausted through the sequence of openings and passageways 86, 104,103,and-l05. The exhaust operation is materially aided by the high pressureventuri arrangement shown in FIG. 8 when this kind of scaveng-. ing isutilized.

The operating cycle for chamber segment is repeated for each of theother chamber segments 72, 73 and 74 in continuing sequence. Thus, aseach chamber segment is rotated through a complete revolution, theintake valve to the chamber segment is opened and a mixture of air andfuel is drawn into the chamber segment. The air-fuel mixture iscompressed and is ignited when the chamber reaches the orientation shownin segment 73 in FIG. 5. The pressure increase. caused by the burning ofthe fuel continues to drive the engine, maintaining rotation of runnermember 45, piston member 56, and shaft 34. At the end'of the cycle thecombustion byproducts are exhaustedv from the chamber segment throughthe exhaust valve, which closes priorto the time that the intake valvefor the chamber'segment opens to draw a new fuel supply into thechamber. In effect, therefore, engine 20 functions much like afour-cylinder two-stroke-cycle internal combustion engine ofconventional type.

There aresome marked differences in the construction and operation ofengine 20, however, as compared with conventional engines of either thelinear piston or rotary piston kind. Because both runner 45 and piston'56 rotate continuously at the same speed about the same main axis 33,the angular movement of the piston gages 62-64 relative to the internalsurface 61 of runner member 45 is extremely limited. Usually, thisangular movement is limited to a range of about 6 to 12, depending onthe engine dimensions, particularly the inner diameter of the runner andthe displacement between axes 33 and 51. Consequently, sealing of thechamber segments 72-75 from each other can be effected more efficientlythan in previously known rotary engines without introducing the extremeproblems of wear and seal maintenance that have long plagued rotarypower devices. Friction between the two principal rotating elements ofengine 20, piston member 56 and runner member 45, is minimal. Thedriving connection between these two principal members, afforded by thepins 77 and slots 78, is disassociated from the portions of the gatemembers that extend into the chamber between the piston member and therunner member and does not add to the sealing problems. The gate membersthemselves move reciprocally toward and away from the main axis 33 ofthe engine and can be sealed by relatively simple seals such as themember 67 to prevent communication between the central portion of pistonmember 56 and the chamber segments around the periphery of the pistonmember.

The heat distribution for engine is quite even, since the workingchamber of the engine is divided into a plurality of segments andcombustion takes place in each of those segments. That is, the multiplefiring points afforded by the four spark plugs 142-145 effectivelyequalizes heating effects around the periphery of engine 20. Thisequalization is made possible by the fact that the engine does not havea stator, in the normal sense of the term, since both of the principalmembers forming the combustion chambers for the engine rotate aroundaxis 33 at the same speed.

Engine 20 is compact in construction and can be made quite light inweight, particularly if high temperature aluminum alloys and likematerials are used in the fabrication of runner 45, piston 56, and gates62-65. Engine 20 can be operated in virtually any desired orientation.Thus, there is no requirement that shaft 34 by oriented in a horizontaldirection as shown in FIG. 2. The shaft can be located at any desiredangle, from a horizontal alignment to a completely vertical alignment.The lubrication needs of the engine are minimal, being confinedprimarily to the main and secondary bearings 29, 39, 52 and 53. Somelubrication may be required for gates 62-65 and can be introducedaxially through the hollow end of shaft 34 and through the center ofpiston 56 as necessary.

Engine 20 may be constructed for liquid cooling if desired. Preferably,however, an air-cooled construction is employed. One suitable coolingarrangement is illustrated in FIG. 1 and comprises a plurality ofannular heat exchanging rings 161 mounted upon the main cylindricalelement 46 of runner member- 45. The mounting should be one whichaffords a good heatexchange contact between rings 161 and runner member45,

A multiplicity of individual heat exchange elements 162 are mountedaround runner member45 between rings 16]. Each of the heat exchangeelements 162 is provided with two or more tapered openings 163 extendingthrough the heat exchange element (FIGS. 1A

and 1B). When engine 20 is in operation, with runner member 45 rotatingrapidly, air is forced through the openings 163 in the heat exchangeelements 162. This provides efficient cooling of the engine without thenecessity for elaborate or expensive cooling equipment. No fan isrequired; runner 45 is its own fan.

FIGS. 9 and 10 illustrate an alternate construction for a four-chamberrotaryengine 220 that is somewhat similar to engine 20 as describedabove but incorporates a number of modifications in the overall engineconstruction. Engine 220 comprises a frame 221 including a base plate222 with a rear pedestal 223 and a front pedestal 224 mounted on thebase plate by suitable means such as the bolts 225. A fixed shaft 226 ismounted in the rear pedestal 223 of engine 220, a mounting pin 227extending transversely through the shaft and through pedestal 223. Thefixed shaft 226 extends across engine 220 through an enlarged opening inpedestal 224. The axis 233 of shaft 226 constitutes the primary axis ofengine 220.

A rear bearing sleeve 228 and a front bearing sleeve 229 are mountedupon the fixed shaft 226, adjacent pedestals 223 and 224 respectively. Arunner member 245 is rotatably mounted upon the two bearing sleeves 228and 229. Runner member 245 comprises a generally cup-shaped element 246having a front end wall 247. A rear end wall member 248 is mounted onthe rim of the cup-shaped element 246. Runner member 245 has a centralopening 249 of generally cylindrical configuration that is symmetricalwith respect to the primary axis 233 of the engine, as best shown inFIG. 10. The front end wall 247 of runner 245 includes an elongatedhollow extension 234 that projects outwardly of the front end of theengine and that constitutes the output shaft of the engine. Shaft 234 isdisposed in-bearing contact with bearing member 229 and is symmetricalwith respect to the primary axis 233 of engine 220.

At the rear or left-hand end of engine 220, as seen in FIG. 9, a thrustbearing plate 235 is mounted around bearing member 228 in engagementwith the outer surface of the end wall element 248 of runner member 245.An end bell 236 is mounted adjacent bearing plate 235, the end bellbeing disposed in encompassing relation to bearing member 228. A spring237 is interposed betweenportions of pedestal 223 and end bell 236,biasing the end bell and bearing plate 235 toward the end wall element228 of runner member 246.

At the front end of engine 220, the construction is similar. A bearingplate 238 engages the outer surface of the end wall 247 of runner member245 and is maintained in engagement with the runner member by an endbell 239 and a spring 241 interposed between the end bell and the frontpedestal 224 of the engine. A bearing sleeve 242 is interposed betweenshaft 234, on the one hand, and bearing plate 238 and end bell 239 onthe other hand. Sleeve 242'extends through the opening in pedestal 224that encompasses shafts 226 and 234.

A cam 252 is affixed to the central portion of the stationary shaft 226in alignment with the central opening 249 in runner member 245. Cam 252and shaft 226 may be of unitary construction, machined from a singlemetal piece. The peripheral surface of cam 252 is circular inconfiguration but the cam is not symmetrical piston member 256 isrotatably mounted upon sleeve 253 within the central opening 249 inrunner 245. Cam 252, bearing sleeve 253, and piston member 256 all haveend surfaces that are disposed in close sealingv relation to the innerend surfaces of the runner end walls 247 and 248. Auxiliary sealingmeans, such as the O-ring seal 268, can be provided for piston member256 and runner member 245 if desired.

As shown in FIG. 10, the inner surface 261 of runner member 245 isgenerally rectangular in configuration with arcuate corners on therectangle. Similarly, the peripheral surface 259 of piston member 256 isof generally rectangular configuration with arcuate corners. As notedabove, however, piston member 256 is essentially symmetrical withrespect'to the secondary axis 251, whereas runner member 245 isessentially symmetrical with respect to the primary axis 233. Thecorners formed by the internal surface 259 of piston member 256 arealigned with but are angularly smaller than the arcuate corners of theinternal surface 261 of runner member 245.

From FIG. it can be seen that piston surface 259 and runner surface 261conjointly define a closed ringlike chamber, around the periphery of thecentral opening 249 of runner member 245,-that varies in radial depthfrom a minimum of virtually zero along an upwardly extending verticalradius from primary axis 233 to a maximum along a downwardly directedvertical radius from the primary axis. Stated differently, the minimumradial depth of the ring-like chamber between the piston and the runner,in engine 220, occurs along one radius takenon the diameter intersectingboth the axes 233 and 251, whereas the maximum radial depth occurs alongthe opposite radius. The I same relation ship obtains in engine 20 (FIG.5).

Engine 220 further comprises four gate members 262, 263, 264 and 265,each mounted within a radial slot in piston member 256 (FIG. 10). Eachof the gate members 26 2-265 extends for the full length of the centralopening 249 in runner member 245, as illustrated by gate members 262 and265 in. FIG. 9. As in the previous embodiment, the'gate members may beprovided with suitable sealing elements along their sides, .althoughthis is not essential in engine 220 because the slots in which the gatemembers are mounted in piston 256 are closed at their inner ends.Springs may be provided to bias gate members 263-265 outwardly intoengagement with the arcuate corners of the internal runner surface 261;on the other hand, for a high speed engine, centrifugal force may berelied upon to maintain the gate members in sealing eng'agement with theinner surface of chamber 249. As best shown in FIG. 10, gate members262-265 divide the ring-like chamber around piston member 256 into fourseparate chamber segments 272, 273, 274 and 275.

As in the previous embodiment, engine 220 includes key means tointerconnect shaft 234, runner member 245, and piston member 256 forconjoint rotation about theprimary axis 233 of the engine. In engine220, shaft 234 constitutes an integral part of runner member 245. Bothshaft 234 and runner 245 are journalled on the sleeve bearings mountedon the fixed shaft 226, assuring conjoint rotation of shaft 234 andrunner member 245 about axis 233. Piston member 256, on the other hand,is keyed to runner member 245. The key means utilized in this instancecomprises a pin 277 projecting inwardly from runner member 245 into anelongated slot 278 in piston member 256. The central portion of slot 278may be widened somewhat to compensate for limited angular displacementbetween runner member 245 and piston member 256 during operation of theengine. A similar pin and slot connection may be provided on theopposite side of the engine.

The rear wall 248 of runner member 245 is provided with four smallintake openings 281, one intake opening for each of the chamber segments272-275. The positions of the intake openings 281 are shown in phantomoutline in FIG. 10, and one intake opening 281 is illustrated in FIG. 9.As shown in FIG. 9, the radial location of the openings 281 .is alignedwith a passageway 282 that extends through bearing plate 235 and endbell 236. An intake conduit 283 mounted in pedestal 223 connects withpassageway 282; conduit 283 is connected to a suitable carburetor orother source of fuel/airmixture (not shown). As shown in FIG. 10, theintake openings are normally masked by piston 256, being exposed totheir respective chamber segments only for a limited arcuate open rangethat coincides, in part, with the position of intake passageway 282(FIG. 10).

The front end wall 247 of runner member 245 includes four small exhaustopenings 284 one for each chamber segment 272-275; The locations of thefour exhaust openings 284 are illustrated by dashed outlines in FIG. 10,and one appears in FIG. 9. The radial orientation of the exhaustopenings 284 is aligned with an exhaust passageway 285 that extendsthrough bearing plate 238 and through the front end bell 239 into anexhaust conduit 286 mounted in the front pedestal 224 of the engine.Conduit 286 is provided with an opening 287 that communicates with anexhaust chamber 288 in pedestal 224. Chamber 288, in turn, opens into afurther exhaust conduit 289 corresponding to conduit 132 in the engineof FIGS. 1-8. Exhaust openings 284 are normally closed off from theirrespective chamber segments 272-275 by piston member 256, being openonly for a limited arcuate rangecoinciding in partwith the location ofexhaust passage 285 (FIG. 10).

Engine 220 includes ignition means comprising four spark plugs 292, 293,294 and 295,'one for each of the chamber segments 272-275. Each of thespark plugs is sealed into a radial opening in runner 245..A fixedelectrical contact 296, connected to a suitable electrical supply, ispositioned to engage each of the spark plugs 292-295 as runner 245rotates during operation of engine 220. Preferably, the fixed contact296 should be mounted for angular adjustment relative to runner 245,

within a limited range, to afford a means for adjusting the timing ofthe engine, since there is no provision in engine 220 for changing thetiming of exhaust or intake. valves.

In considering the operation of engine 20, it may be assumed that runner245 and piston 256 start from the position shown in FIG. 10. Rotation ofthe engine is in a clockwise direction as viewed in FIG. 10. As theengine rotates, the intake opening 281 for chamber segment 274 comesinto alignment with intake conduit 282 and admits a mixture of fuel andair into chamber segments 274. At the time the fuel-air mixture isadmitted into chamber segment 274, the chamber segment is relativelylarge in volume.

Continuing rotation of runner 245 and piston 256 reduces the volume ofchamber segment 274, as illustrated by chamber-segment 275, compressingthe fuel and air mixture. As chamber 274 reaches its minimum volume, atthe position illustrated in FIG. by chamber segment 272, spark plug 294engages the fixed electrical contact 296 and fires, igniting thefuel/air mixture in chamber segment 274. As the mixture in chamber 274burns, it increases the pressure in the chamber segment and exerts asubstantial force against the lead gate 265 for chamber 274, tending todrive gate member 265 and pistonv member 256 in a direction to continueclockwise rotation of the engine. The driving force is transmitted torunner 245 by the keying means comprising pin 277 and slot 278.

Continuing rotation of the engine moves chamber segment 274 through theposition shown in FIG. 10 for chamber segment 273 and ultimately bringsthe exhaust opening 284 for chamber segment 274 into alignment with theexhaust conduit 285. The hot gases from chamber 274 are exhaustedthrough the passageway 285, conduit 286, chamber 288, and conduit 289(FIG. 9). Scavening of the exhaust gases may be aided by a high pressureventuri arrangement of the kind described above in connection with FIG.8.

The operating cycle for chamber 274 is repeated for each of the otherchamber segments 272, 273 and 275 in continuing sequence. As eachchamber segment bustion engine 320 constructed in accordance with anadditional embodiment of the invention. Engine 320 comprises acylindrical runner 345 having a central opening 349 of generallytriangular configuration, but with arcuate corners, opening 349 beingsubstantially symmetrical with respect to a secondary axis 351 for theengine. The primary axis 343 for engine 320 is the axis of a main shaft334. Shaft 334 is a splined shaft with a piston member 356 mounted onthe shaft within the central opening 349 of runner 345. The externalsurface 359 of piston member 356 is of generally triangularconfiguration, with arcuate corners, and is symmetrical with respect tothe primary axis 333 of the engine.

Engine 320 is equipped with three gate members 363, 364 and 365, eachmounted in an elongated slot in piston member 356 that is aligned withone of the arcuate corners of the piston member. The inner edge of gate363 is engaged by one or more guide pins 366 that I extend through guideopenings in piston member 256 rotates through a complete cycle of 360,the intake opening 281 to the chamber segment comes into alignment withintake conduit 282 and a mixture of air and fuel is drawn into thechamber segment. The air-fuel mixture is compressed and is ignited whenthe spark plug for the chamber segment engages contact 296. The periodicpressure increases caused by the burning of the fuel in the'chambersegments drive the engine, maintaining continuous rotation of pistonmember 256, runner member 245 and output shaft 234. At the end of thecycle for each chamber segment, the combustion byproducts are exhaustedfrom the chamber segment when the exhaust opening 284 of that chambersegment comes into alignment with exhaust conduit 285. Thus, as in thecase of engine 20, engine 220 functions in accordance with the basicoperating cycle of a fourcylinder two-stroke-cycle internal combustionengine.

In engine 220, as in engine 20, the angular movement of gates 262 and265 relative to the internal surface 261 of runner member 245 isextremely limited. Accordingly, the friction and wear at the points ofcontact between the piston gates and the runner are quite limited, sothat maintenance of a seal at each of the gates is much easier than withrotary engines of conventional construction. Driving connections betweenthe principal members of the engine are disassociated from the gatemembers and do not add to the sealing and in shaft 334. Similar guidepins 367 and 368 are provided with gates 364 and 365 respectively. Thediametricaldistance for each combination of a gate and its guide pinsremains constant during rotation of engine 320, so that the guide pinsserve to maintain the gates in constant contact with the inner surface361 of the central opening 349 in the runner member 345. As in theprevious embodiments, runner member 345 is provided with end walls (notshown) and the gate members 363-365 extend for the full axial length ofopening 349 and into sealing engagement with the end walls of the runnermember. Furthermore, piston 356 extends completely across centralopening 349, in an axial direction, and into sealing engagement with theend walls of runner member 345.

Gates 363-365 divide the ring-like chamber between piston surface 359and runner surface 351 into three chamber segments 373, 374 and 375.There are three spark plugs 383, 384 and 385, one for each of the threechamber segments 373-375. A fixed electrical contact 386 is positionedto energize each of the spark plugs at one point during rotation ofrunner member 345. En-

"gine 320 is also provided with. intake and exhaust means communicatingwith chamber segments 373-375; the intake and exhaust arrangements maycorrespond to those described above for either of engines 20 and 220 andhave not been illustrated.

The operation of engine 320 is essentially similar to the enginesdescribed above except that there are only three chamber segments sothat the engine operates in a manner similar to a three piston engine ofconventional type. Starting from the position shown in FIG. 11, an airfuel mixture is drawn into chamber segment 375. The mixture iscompressed as the engine rotates,

rotation being in a clockwise direction as shown in FIG. ll. Whenchamber 375 reaches the position illustrated for chamber 373, its sparkplug 385 engages contact 386 and the spark plug fires, igniting theair/fuel mixture in the chamber segment.

The resultant burning of the fuel in chamber segment 375 exerts asubstantial force against the lead gate 363 for the chamber, driving theengine toward continuing rotation in a clockwise direction. As runner345 and piston 356 continue their rotation, chamber segment 375 isbrought to the position shown in FIG. 11 for chamber segment 374. Anexhaust port is opened, the burned gases are exhausted from the chamber375, and the cycle repeats. The operating cycle for each of the othertwo chamber segments 373 and 374 is the same as described for chambersegment 375. Thus, engine 320 operates like a three-cylinder two-strokecycle internal combustion engine.

Each of the three internal combustion engines 20, 220 and 320 describedabove is compact, light in weight, and capable of a high power output.In each of the engines, friction between the principal elements of theengine is quite limited, particularly because the friction between therotating piston and the rotating runner is greatly reduced because bothrotate simultaneously. Each of the engines affords balanced firingaround the periphery of the engine, equalizing heating of the runner andthe piston. It will be recognized that each of the engines can beconverted to a pump by eliminating the spark plugs and by driving thedevice from an external source. Any one of the engines can be operatedin any desired orientation.

The use of pistons and runners of substantially polygonal configurationwith arcuate corners, as in engines 220 and 320, allows for shaping ofthe chamber segments to optimize combustion in the engine. With eitherpolygonal or circular pistons and runners, the total number of chambersegments can be selected to suit the power range and the operatingcharacteristics required of the engine.

I claim:

l. A rotary power device comprising:

a frame;

a cylindrical runner member, having end walls closing off both ends of acentral opening therein, mounted on said frame for rotation about aprimary axis;

a piston member, mounted in the central opening in said runner memberand having end walls disposed in close sealing relation to the end wallsof said runner member;

the peripheral surface of said piston member and the internal surface ofsaid runner member being symmetrical with respect to axes that areparallel to but displaced from each other, so that said surfacesconjointly define a closed ring-like chamber varying in radial depthfrom a minimum along a first radius taken on a diameter intersectingboth said axes to a maximum along a second oppositely directed radius,one of said axes of symmetry coinciding with said primary axis;

fluid inlet means and fluid outlet means communicating with saidchamber, said fluid outlet means comprising a plurality of exhaustopenings in one end wall of said runner member, one exhaust opening foreach chamber segment;

a plurality of gate members, mounted in said piston for limited movementredially thereof and extending outwardly of the piston member throughsaid chamber into engagement with the inner surface of said runnermember, each gate member extending for the full length of said centralopening so that said gate members divide said chamber into acorresponding plurality of chamber segments;

and key means, interconnecting said runner member and said piston memberfor conjoint rotation, whereby the effective volume of each chambersegment varies continuously between a minimum and a maximum.

2. A rotary power device, according to claim 1, in which said fuel inletmeans comprises a plurality of inlet openings in the other end wall ofsaid runner member, one inlet opening for each chamber segment.

3. A rotary power device, according to claim 2, in which said inlet andexhaust openings for each chamber segment are angularly displaced fromeach other.

4. A rotary power. device, according to claim 3, in which said inlet andexhaust openings for each chamber segment are normally masked by saidpiston member except for a limited arcuate open range in the rotation ofsaid piston and runner members, the arcuate open ranges for the inletand exhaust openings of each chamber segment being angularly displacedfrom each other. I

5. A rotary power device, according to claim 2, and further comprising:

a corresponding plurality of normally closed inlet valves, one mountedin each inlet opening;

inlet valve actuating means for actuating each inlet valve to opencondition during only a limited arcuate inlet range in the rotation ofsaid piston and runner members;

a corresponding plurality of normally closed exhaust valves, one mountedin each exhaust opening;

and exhaust valve actuating means for actuating each exhaust valve toopen condition during only a' limited arcuate exhaust range in therotation of said piston and runner members, said inlet range and saidexhaust range being angularly displaced from each other.

6. A rotary power device, according to claim 5, in which each of saidvalves includes a cam follower projecting externally of said runnermember, and in which said inlet valve actuating means comprises astationary cam mounted on said frame in position to actuate said camfollowers of said inlet valves at a given point in the rotation of saidrunner member and said exhaust valve actuating means comprises astationary cam mounted on said frame in position to actuate said camfollowers of said exhaust valves at a given point in rotation of saidrunner member.

7. A rotary power device, according to claim 6, in which each of saidcams comprises an annular cam ring, and further comprising means forangularly adjusting the position of each cam ring to control the timingof the opening of said inlet valves and said exhaust valvesindependently of each other.

8. A rotary power device, according to claim 6, comprising an internalcombustion engine, and further comprising:

means for introducing a fuel-air mixture into the individual chambersegments of said device, in sequence, through said fluid inlet means, aseach chamber segment passes a first rotational position;

and ignition means for igniting the fuel-air mixture in each chamber ata second rotational position for that chamber segment displaced asubstantial angular distance from said first rotational position.

9. A rotary internal combustion engine, according to claim 8, in whichsaid ignition means comprises a plurality of spark plugs mounted on saidrunner, each spark plug extending into a respective one of said chambersegments, and electrical contact means for firing each spark plug eachtime said runner reaches said second rotational position.

10. A rotary power device according to claim 1 and further comprising arotary shaft having an axis coincident with the primary axis of saiddevice and with the axis of symmetry of the internal surface of saidrunner member, said rotary shaft being affixed to said runner member forconjoint rotation therewith, and a stationary shaft extending coaxiallythrough said central opening in said runner member, said stationaryshaft having a circular cam affixed thereto concentric with the axis ofsymmetry of said piston member, said circular cam projecting into thecentral opening in said runner member, and said piston member beingrotatably mounted upon said circular cam member.

1. A rotary power device comprising: a frame; a cylindrical runnermember, having end walls closing off both ends of a central openingtherein, mounted on said frame for rotation about a primary axis; apiston member, mounted in the central opening in said runner member andhaving end walls disposed in close sealing relation to the end walls ofsaid runner member; the peripheral surface of said piston member and theinternal surface of said runner member being symmetrical with respect toaxes that are parallel to but displaced from each other, so that saidsurfaces conjointly define a closed ring-like chamber varying in radialdepth from a minimum along a first radius taken on a diameterintersecting both said axes to a maximum along a second oppositelydirected radius, one of said axes of symmetry coinciding with saidprimary axis; fluid inlet means and fluid outlet means communicatingwith said chamber, said fluid outlet means comprising a plurality ofexhaust openings in one end wall of said runner member, one exhaustopening for each chamber segment; a plurality of gate members, mountedin said piston for limited movement redially thereof and extendingoutwardly of the piston member through said chamber into engagement withthe inner surface of said runner member, each gate member extending forthe full length of said central opening so that said gate members dividesaid chamber into a corresponding plurality of chamber segments; and keymeans, interconnecting said runner member and said piston member forconjoint rotation, whereby the effective volume of each chamber segmentvaries continuously between a minimum and a maximum.
 2. A rotary powerdevice, according to claim 1, in which said fuel inlet means comprises aplurality of inlet openings in the other end wall of said runner member,one inlet opening for each chamber segment.
 3. A rotary power device,according to claim 2, in which said inlet and exhaust openings for eachchambEr segment are angularly displaced from each other.
 4. A rotarypower device, according to claim 3, in which said inlet and exhaustopenings for each chamber segment are normally masked by said pistonmember except for a limited arcuate open range in the rotation of saidpiston and runner members, the arcuate open ranges for the inlet andexhaust openings of each chamber segment being angularly displaced fromeach other.
 5. A rotary power device, according to claim 2, and furthercomprising: a corresponding plurality of normally closed inlet valves,one mounted in each inlet opening; inlet valve actuating means foractuating each inlet valve to open condition during only a limitedarcuate inlet range in the rotation of said piston and runner members; acorresponding plurality of normally closed exhaust valves, one mountedin each exhaust opening; and exhaust valve actuating means for actuatingeach exhaust valve to open condition during only a limited arcuateexhaust range in the rotation of said piston and runner members, saidinlet range and said exhaust range being angularly displaced from eachother.
 6. A rotary power device, according to claim 5, in which each ofsaid valves includes a cam follower projecting externally of said runnermember, and in which said inlet valve actuating means comprises astationary cam mounted on said frame in position to actuate said camfollowers of said inlet valves at a given point in the rotation of saidrunner member and said exhaust valve actuating means comprises astationary cam mounted on said frame in position to actuate said camfollowers of said exhaust valves at a given point in rotation of saidrunner member.
 7. A rotary power device, according to claim 6, in whicheach of said cams comprises an annular cam ring, and further comprisingmeans for angularly adjusting the position of each cam ring to controlthe timing of the opening of said inlet valves and said exhaust valvesindependently of each other.
 8. A rotary power device, according toclaim 6, comprising an internal combustion engine, and furthercomprising: means for introducing a fuel-air mixture into the individualchamber segments of said device, in sequence, through said fluid inletmeans, as each chamber segment passes a first rotational position; andignition means for igniting the fuel-air mixture in each chamber at asecond rotational position for that chamber segment displaced asubstantial angular distance from said first rotational position.
 9. Arotary internal combustion engine, according to claim 8, in which saidignition means comprises a plurality of spark plugs mounted on saidrunner, each spark plug extending into a respective one of said chambersegments, and electrical contact means for firing each spark plug eachtime said runner reaches said second rotational position.
 10. A rotarypower device according to claim 1 and further comprising a rotary shafthaving an axis coincident with the primary axis of said device and withthe axis of symmetry of the internal surface of said runner member, saidrotary shaft being affixed to said runner member for conjoint rotationtherewith, and a stationary shaft extending coaxially through saidcentral opening in said runner member, said stationary shaft having acircular cam affixed thereto concentric with the axis of symmetry ofsaid piston member, said circular cam projecting into the centralopening in said runner member, and said piston member being rotatablymounted upon said circular cam member.